Improvement in devices for overcoming dead-centers



.JOHN COY.

Improvement in Device for Overcoming Dead-Centers.

No. 126,526. Patented May 7,1872.

UNITED STATES PATENT OFFICE.

JOHN COY, OF OSWEGO, NEW YORK.

IMPROVEMENT IN DEVICES FOR-OVERCOMING DEAD-CENTERS.

Specification forming part of Letters Patent No. 126,526, dated May 7,187-2.

Specification describing a Device for Overcoming Dead-Centers andpreventing back motion of crank-wheels, invented by JOHN (JOY, ofOswego, in the county of Oswego and State of New York.

The invention will first be described in connection with all that isnecessary to a full understanding thereof, and then clearly pointed outin the claim.

' Figure l is a side elevation. Fig. 2 is a top view.

A is a sliding head; B, its guide; 0, a rigid frame-piece, to which itis attached; and D, the pitman. This pitman is pivoted 011 a pin, d,which passes through a disk, E, and radial strap F. The disk E has anannular flange, e,

011 the side next the pitman, and around the periphery thereof, andagainst this flange falls loosely a cam, F, pivoted on the pitman. G isanother strap, pivoted to rigid frame-piece O, and connected to thestrap F by tongueand-groove joint. The tongue is not fastened closelyand tightly in the groove, but allowed end-play.

The mode of operation is as follows: As long as the disk E moves in thedirection of the increase of the pivoted cam F the latter will presentno obstruction, but the moment that a reverse movement is attempted thecam acts as a brake and locks the disk. Again, when the pitman arrivesat a dead-center the straps F G, having end-play at their joint, fallout of line and throw said pitman out of line with the head A. This, ofcourse, relieves the pitman instantaneously from the dead-center.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

l. A pitman provided with pivoted cam F, in combination with disk Ehaving flange e, as and for the purpose described.

2. The combination, with the pitman, of straps F G, pivoted togetherloosely and with end-play, as and for the purpose set forth.

' JOHN OOY.

Witnesses:

AARON CoLNoN, GEo. L. THOMAS.

